David, great work - thanks!
Gerhard OE3GBB -----Ursprüngliche Nachricht----- Von: David Rowe [mailto:da...@rowetel.com] Gesendet: Montag, 13. Februar 2012 02:56 An: freetel-codec2@lists.sourceforge.net Betreff: [Freetel-codec2] 1500 bit/s release Hello List, I am working on a 1400 bit/s release but thought this interim version at 1500 bit/s might be useful: svn co -r 306 https://freetel.svn.sourceforge.net/svnroot/freetel/codec2-dev Using c2sim: ./c2sim ../raw/hts1a.raw --1400 -o hts1a_1400_c2sim.raw Or separate encoder/decoder: ./c2enc 1400 ../raw/hts1a.raw hts1a_1400.c2 ./c2dec 1400 hts1a_1400.c2 hts1a_1400_c2dec.raw Yeah I know it says 1400 in the file names and flags above but it's actually 1500 at present, 60 bit/s per frame at 40ms frames. While messing about with quantising LSP differences and VQ I discovered that a 40ms update of LSPs actually sounds OK. Better than I expected at least. I didn't believe it at first (normally 20ms updates are reqd in other codecs) so I completed a separate encoder/decoder version to make sure I wasn't fooling myself. Then it occurred to me that a working 1500 bit/s version (separate encoder and decoder) might be useful to others. Some samples attached. This version uses the original 36 bit scalar quantiser so should be easy to drop the bit rate using VQ if it works out that 40ms updates are really OK. Cheers, David ------------------------------------------------------------------------------ Try before you buy = See our experts in action! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-dev2 _______________________________________________ Freetel-codec2 mailing list Freetel-codec2@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freetel-codec2
